DVD Write types
CAV = Constant Angular Velocity, the DVD is written at a constantly increasing speed.
CLV = Constant Linear Velocity, the DVD is written at a constant speed.
ZCLV = Zone Constant Linear Velocity, the DVD is divided into zones. After each zone the write speed is increased.
PCAV = Partial Constant Angular Velocity, the DVD is being written at an increasing speed until a certain speed. After this speed it will not increase anymore.